South-Western and Central Asia

     The Climate of South-Western Asia. The climate of South-Western Asia varies with the latitude, the distance from the sea and the altitude.
The January isotherm of 0°C skirts the southern edge of the Low­land of Turan, then bends southward toward the Plateau of Iran and continues along the coastline of Asia Minor. In many places, therefore, occur frosts in winter. Summers in these regions are in­tensely hot. There is very little rain on the Turan Lowland, the Pla­teau of Iran and the central regions of Asia Minor. In these places the climate is of the desert type.
Along the coasts of Asia Minor facing the Mediterranean and Aegean Seas the climate is the same as in peninsular Southern Europe Mediterranean, with dry, hot summers and warm, rainy winters.
The Black Sea coast of the Caucasus also enjoys a subtropical climate. In contrast to the Mediterranean regions, however, the Black Sea coast receives much rain at all seasons. The prevailing westerly winds carrying moist air from the sea are blocked by the tall Caucasus Mountains. For this reason the slopes facing the Black .Sea have a high rainfall.
The Climate of Central Asia. In Central Asia the winter tempe­ratures are almost as low as in some regions of Siberia. In depres­sions the temperature is rather high in summer. At higher altitudes, however, it varies greatly, the days being hot, the nights cold.
In these interior regions, shut off from the sea by mountains, the annual rainfall barely reaches 200 mm, only the mountain slopes receiving more. There is snow in winter, but it evaporates without even melting in the dry, cool air.
Thus, Central Asia has the sharp continental climate of the tern-, perate zone deserts.

As the regions north of the Himalayas are cut off from the moist air of the Indian Ocean by the enormous barriers of the Tibetan Pla­teau and the Himalayas, the climate in these parts is rigorous and dry. Winter frosts in Tibet sometimes reach 30—35°C below zero, though it lies in the same latitude as the Mediterranean Sea and the southernmost points of Europe, where the climate is subtropical.
It is very hot in the sun in summer, but cold in the shade. Night frosts are common even in July, snow-storms occuring in summer.
Here is N. M. Przhevalsky's description of summer days in Tibet: "On clear and calm days it is warm, even hot, and the sun is scorch­ing. But as soon as a cloud appears, especially if it brings rain, or a wind blows, it becomes cold at once. Such changes occur several times a day. Clear and calm nights are accompanied by slight frosts throughout the summer. On a single June day the scene may be a winter one in the morning and a truly summer one at noon.
Fierce storms are frequent. They fill the air with clouds of dust and sand, sometimes even lifting small stones.
Questions and Assignments.

• Trace the January isotherm of 0°C on the climate map of Asia.
  Compare it-with that of Europe.
• If your school is in the Asiatic part of the U.S.S.R., determine
  the average temperatures for January and July in your neighbour­
  hood, using your weather observations or climate map to do so. Show
  the annual temperature variation and the rainfall.